Any discharge from an eye is a sign of infection. Unless, the white might possibly be bits of shed skin. A vet can examine the eye close up with a opthalmoscope (sp?) to look for signs of injury, scarring, etc., and can also prescribe the appropriate antibiotic ointment to treat it. You can do a couple of things to make him more comfortable too. Check your cage humidity...mist more often (gently for a longer time is better) to help the cham clean its eye on its own. Dry air can irritate eyes too. If the eye gets crusted or stuck shut, you can help him clean it by squirting sterile optical saline (no preservatives) onto the eye and let him work the eye around under the lid.